1. Field of the Invention
The present invention relates to an exposure apparatus, particularly relates to the exposure apparatus in which a plurality of scanning electrodes of a line shape of a direction corresponding to a main-scanning direction are provided in a sub-scanning direction, and a plurality of data electrodes of a direction corresponding to the sub-scanning direction are provided in the main-scanning direction, and a light emitting element which emits light by receiving voltage application of the scanning electrode and the data electrode is formed at an intersecting position of the scanning electrode and the data electrode.
2. Description of the Related Art
There hitherto has been the exposure apparatus in which the light emitting elements are arranged in the main-scanning direction, for the exposure apparatus which exposes a photosensitive member to record a picture image. In the exposure apparatus, unevenness in the shape of a streak in the sub-scanning direction is generated on the picture image by variations in light emitting quantity of each element. Therefore, there is a technique which averages the variations in the light emitting quantity of each element to eliminate the unevenness in the shape of the streak in a manner that arranges a plurality of element rows in the sub-scanning direction and repeatedly exposes one main-scanning line by the plurality of element rows.
In this case, one of a pair of electrodes (an anode and a cathode) which applies a predetermined voltage (or current) to the light emitting element to emit light is provided in each element row, the plurality of light emitting elements which constitutes the element row and are arranged in the main-scanning direction are used as the common scanning electrode, the other electrode is provided so as to intersect the plurality of scanning electrodes which are provided in each element row, and the plurality of light emitting elements which are arranged between the plurality of element rows in the sub-scanning direction are sometimes used as the common data electrode.
However, in the related art, because the voltage is applied by the same data electrode in the plurality of light emitting elements which exposes the same pixel element and are arranged in the sub-scanning direction, in case that the variations in characteristics of the data electrodes or a driving voltage from a driver are caused in each data electrode, even if each light emitting element is formed uniformly, there has been a problem that the unevenness in the shape of the streak is generated in the sub-scanning direction. Though it is also considered that quantity of light or print density in each pixel element is measured, and the driving voltage (or current) value in each element, exposure time, or the like is adjusted in each element to suppress the variations in exposure, it is not feasible due to a necessity of a complicated control system.
In view of the foregoing, it is an object of the present invention to provide an exposure apparatus which can decrease the unevenness in the shape of the streak of the sub-scanning direction which is caused by the variations in the characteristics of the data electrode or the driver and be feasible with a simple arrangement.
In order to achieve the above-described object, an exposure apparatus according to the invention in which a plurality of scanning electrodes of a line shape of a direction corresponding to a main-scanning direction are provided in a sub-scanning direction, a plurality of data electrodes of a direction corresponding to the sub-scanning direction are provided in the main-scanning direction, and a light emitting element which emits light by receiving voltage application of the scanning electrode and the data electrode is formed at an intersecting position of the scanning electrode and the data electrode, which is characterized in that each of the plurality of data electrodes is provided to have a predetermined angle to the sub-scanning direction so that exposure positions where exposure is carried out by the light emitting elements formed in the different data electrodes become substantially the same position in the sub-scanning.
An exposure apparatus according to the invention comprises a plurality of scanning electrodes which are arranged in a direction corresponding to a sub-scanning direction and formed in the shape of a line in a direction corresponding to a main-scanning direction and a plurality of data electrodes which is provided so as to intersect the plurality of scanning electrodes, and a light emitting element which emits light by receiving voltage application of the scanning electrode and the data electrode is formed at an intersecting point of the scanning electrode and the data electrode. In more detail, by providing each of the plurality of data electrodes to have a predetermined angle to the sub-scanning direction such that exposure positions where exposure is carried out by the light emitting elements formed in the different data electrodes become substantially the same position in the sub-scanning, when the sub-scanning is carried out in the exposure, since the same pixel element is exposed repeatedly (multiple exposure) by the light emitting elements formed in the different data electrodes, even if variations in the characteristics of the data electrode or a driving voltage from the driver in each data electrode are generated, an influence of the variations is averaged and the unevenness in the shape of the streak in the sub-scanning direction can be decreased. The exposure apparatus can be realized only by obliquely arranging the data electrode relative to the sub-scanning direction, and a complicated control system is not required.
In the exposure apparatus, the scanning electrode may be provided to form a predetermined angle to the main-scanning direction.
In the exposure apparatus, an organic electroluminescence element, an inorganic electroluminescence element, or a liquid crystal element having a light emitting function can be used as the light emitting element.